1. T cells in the immune system can be categorized into different types. What type of T cell directly kills infected body cells?

A. Helper T cells
B. Cytotoxic T cells
C. Regulatory T cells
D. Memory T cells

Correct answer: B

Rationale: Cytotoxic T cells directly kill infected body cells. These T cells recognize and destroy cells that are infected with viruses or other pathogens. They are crucial for eliminating threats within the body. Helper T cells, on the other hand, assist in coordinating the immune response by activating other immune cells. Regulatory T cells help maintain immune tolerance and prevent autoimmune reactions. Memory T cells are responsible for 'remembering' specific pathogens to mount a faster and stronger immune response upon re-exposure. Therefore, cytotoxic T cells are the correct answer as they directly target and kill infected cells.

2. Which of the following is the main function of the skin?

A. To protect the body from harm
B. To regulate body temperature
C. To produce hormones
D. To sense touch, temperature, and pain

Correct answer: A

Rationale: Rationale: A) To protect the body from harm: The skin acts as a physical barrier that protects the body from external threats such as pathogens, UV radiation, and physical injuries. It helps prevent infections and dehydration, making it a crucial function of the skin. B) To regulate body temperature: While the skin does play a role in regulating body temperature through processes like sweating and vasodilation/vasoconstriction, its primary function is protection. C) To produce hormones: Hormone production is primarily carried out by endocrine glands such as the pituitary gland, thyroid gland, and adrenal glands, not the skin. D) To sense touch, temperature, and pain: The skin contains sensory receptors that allow us to perceive touch, temperature, and pain, but this function is secondary to its main role of protecting the body from harm.

3. What type of bone is the kneecap (patella)?

A. Long bone
B. Short bone
C. Flat bone
D. Irregular bone

Correct answer: B

Rationale: The correct answer is B: Short bone. The kneecap, or patella, is classified as a short bone because it is roughly cube-shaped and is composed of spongy bone enclosed by a thin layer of compact bone. Short bones provide support and stability with limited motion, making them ideal for protecting joints like the knee. Long bones are typically elongated, flat bones are thin and curved, and irregular bones have complex shapes. Understanding the classification of bones can help in identifying their functions and structural characteristics.

4. In meiosis I, how are sister chromatids distinguished from homologous chromosomes?

A. Sister chromatids share the same centromere, while homologues have different centromeres.
B. Sister chromatids have identical DNA sequences, while homologues have slightly different sequences due to crossing over.
C. Sister chromatids repel each other, while homologues attract each other during synapsis.
D. Sister chromatids separate during anaphase I, while homologues separate during anaphase II.

Correct answer: B

Rationale: While sister chromatids are identical copies of the same chromosome, homologous chromosomes are paired copies, each inherited from one parent. Crossing over during meiosis I can lead to slight differences in their DNA sequences.

5. As a manager, she focuses her energy on both the quality of services rendered to the patients

A. Country club management
B. Organization man management
C. Team management
D. Authority-obedience management

Correct answer: B

Rationale: The correct answer is 'B: Organization man management.' This type of management focuses on maintaining the efficiency and structure of an organization. In this scenario, the manager's emphasis on the quality of services aligns with the principles of organization man management, which prioritizes the coordination of tasks and resources to achieve optimal results within the organization. This contrasts with 'Country club management,' which emphasizes employee satisfaction over task accomplishment; 'Team management,' which focuses on collaboration and teamwork; and 'Authority-obedience management,' which centers on strict hierarchical control. Therefore, the most appropriate choice is 'B: Organization man management.'

6. What is the purpose of the spindle apparatus in cell division?

A. To separate sister chromatids
B. To move chromosomes to opposite poles of the cell
C. To form a new nuclear envelope around each daughter cell
D. To synthesize new DNA

Correct answer: B

Rationale: Rationale: The spindle apparatus is a structure composed of microtubules that plays a crucial role in cell division (mitosis and meiosis). Its main purpose is to ensure the proper separation and distribution of chromosomes to opposite poles of the cell during cell division. This process is essential for the formation of two genetically identical daughter cells in mitosis or four haploid daughter cells in meiosis. Option A is incorrect because the separation of sister chromatids specifically refers to the role of the kinetochore fibers within the spindle apparatus. Option C is incorrect because the formation of a new nuclear envelope occurs after the chromosomes have been properly segregated. Option D is incorrect because DNA synthesis does not occur within the spindle apparatus; it takes place during the S phase of the cell cycle.